#!/usr/bin/env node

const mysql = require('mysql2/promise');

let con = mysql.createPool({
  host:'localhost',
  user:'root',
    password:'ddd',
    database:'test'
});

async function getAreas(){
  const sql = 'select * from areas';

  let [rows] = await con.execute(sql);

  return rows
}

async function addAreas(areaName){
    const sql = `insert into areas(area_name) values('${areaName}')`;
    let [rows] = await con.execute(sql);
    return rows;
}

async function updateAreas(oldName,newName){
    const sql = `update areas set area_name = '${newName}' 
      where area_name = '${oldName}'`;
      let [rows] = await con.execute(sql);
      return rows

}

async function delAreas(areaName){
    const sql = `delete from areas where area_name = '${areaName}'`;

    let [rows] = await con.execute(sql);

    return rows

}


(async function (){
  //await addAreas('英国');
  //await updateAreas('英国','大不列颠');
  await delAreas('大不列颠');
  console.log(await getAreas());
})();
